The Summit 1974 ice core is a short core. Little has been published on this core, but an excellent reference 
for any of the GISP cores is:

Langway, C.C., Jr., H. Oeschger, and W. Dansgaard (eds.), 1985. 
Greenland ice core: Geophysics, geochemistry and environment: 
Geophysical Monographs, v. 33, American Geophysics Union, Washington D.C.